Bras are frozen, boys are chased and parents are duped in "Sleepover," a good-hearted 'tween comedy hampered by uneven direction and a misguided plot twist.

Directed by Joe Nussbaum, who made the wonderful short "George Lucas in Love," and written by Elisa Bell ("Vegas Vacation"), "Sleepover" provides some insight into the mind-set of a modern 14-year-old girl. Lead character Julie, played by "Spy Kids" star Alexa Vega in a solid, winning performance, is at a juncture where boys and popularity have started to matter, but childhood ties still rule.

Julie and her three slumber-party guests might have been content to play dress-up and eat pizza had a group of more popular girls not challenged them to a scavenger hunt. With rights to the cool high school lunch table at stake, the girls decide to leave the house and enter some dubious situations.

Luckily (and a little too conveniently for the plot), Julie's protective mom (Jane Lynch, from "A Mighty Wind") has left them in the care of Julie's dad. Played by Jeff Garlin from "Curb Your Enthusiasm," Dad is a likable lug too obsessed with installing a water-filtration system to notice the girls stealing out a window and over a trellis.

Among their tasks is getting a pair of boxer shorts from the cutest boy in town (Sean Faris, who could be Tom Cruise's long-lost son). This entails Julie seeing him naked. Far more unsettling, however, is a challenge that has Julie posing as an adult woman on an Internet site to arrange a meeting with a man at a nightclub. In this era of Internet predators, this setup is creepy. When Julie does meet the man, he turns out to be her teacher, who agrees to pose for a snapshot with the girls. As if! Any teacher in his right mind would run for the exit as soon as he spotted the girls.

The rest of the film is pretty tame and girl-positive. Julie is as concerned with her best friend moving away as she is with the dreamboat, and the pals are quite supportive of each other. The girls boost the spirits of their overweight friend (Kallie Flynn Childress, lovely and charismatic), who thinks boys will never like her.

Vega and Lynch create some believable mother-daughter moments. The mother knows that Julie has left the house against her wishes but also that she has returned unharmed, so she doesn't press things. Her daughter, hinting at what she'll be like in later adolescence, pretends to be hurt that her mother doesn't trust her, playing off their dynamic to try to keep herself out of trouble.

First-time feature director Nussbaum shows his rookie status at times, especially when he allows a few of the supporting players to overact outrageously. These young actors shouldn't have to take the blame. Keeping them in check is the director's responsibility.